FlattenLayer

FlattenLayer[] represents a net layer that flattens any input array into a vector.

FlattenLayer[n] represents a net layer that flattens its input to level n.

FlattenLayer[{{s11,s12,…},{s21,s22,…},…}] represents a net layer that flattens its input by combining all levels sij to make each level i in the result.

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